This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. We have developed a novel inducible mouse model of hydrocephalus with 100% penetrance. As a result, we have the unique ability to investigate early pathogenic changes in the development of hydrocephalus. Through the use of electron microscopy, we hope to elucidate early ultrastructural changes that lead to the development of hydrocephalus.